Britain's only major privatised exam board is selling computer software and textbooks designed to help pupils get the "highest possible grades" on one of its qualifications.
Edexcel is offering schools with 60 students on its new diploma in digital applications courses the chance to buy all the resources for one module for pound;950 plus VAT.
It is also promoting an interactive pack and CD-roms for students and teachers. The materials are designed to support teaching, "ensuring students of all levels achieve the highest possible grades".
The move is believed to be the first time an exam board has published textbooks or computer materials for its own courses. The revelation will focus further controversy on the relationship between Edexcel and its owner, Pearson, the world's largest educational publishing company.
A rival publisher said: "Edexcel is blurring the line between being a qualifications provider and being a publisher.
"My other worry is that you are undermining the integrity of the examination if, as an exam board, you publish material that says this is how you pass the examination."
Another publisher said: "This is a murky grey area."
The qualification, known as "DiDA", will replace general national vocational qualifications in ICT in 2007 and is worth four GCSEs in the league tables.
Some 1,200 secondaries are estimated to have started teaching it and the resources can be bought under the Government's "e-learning credit" scheme, which funds free educational software in schools.
Interactive students' CD-roms cost pound;250 plus VAT per school for each of the course's four modules. A CD-rom for teachers costs the same. Schools can also buy an "interactive students' pack" at pound;10.99 plus VAT per student.
A spokeswoman from Edexcel said it was producing a range of high quality support materials for DiDA which are among the cheapest resources on the market.
"Clearly the choice of materials remains with schools and colleges who can use their early learning credits to purchase the materials," said the spokeswoman.